Liquid sealing compound



Patented Aug. 24, 1943 Arthur La Rue Parker, Cleveland, Ohio No Drawing. Application March 24, 1941, Serial N0. 385,009

4 Claims. (01. 252-243) This invention relates to a sealing composition which can be applied in liquid form to surfaces which are to operate in conjunction with one another for the purpose of preventing the passage of liquids such as gasoline, oil, water, de-icer fluids, and the like; and which must be capable of assuring the later easy separation of said parts.

A preferred composition is composed of the following ingredients:

1 Parts Solution of blown castor oil in an alcoholtype solvent (25 parts oil and 75 parts solvent) Chemically-neutral soft linseed oil soap in saturated solution in ethyl alcohol 3.3

Aluminum stearate in saturated solution in toluene 3 this solubility steadily decreases in proportion as' the oil is blown. It is preferred that the heating and blowing be continued until the oil has polymerized to the maximum extent. In particular, it has been found that the blown castor oil known commercially as Hydronamic 781" has consistency and other characteristics which are excellently adapted for this employment. 7

This blown castor oil is introduced in the form of a solution, which in the preferred form contains 25 parts of the castor oil to 75 parts of a solvent of alcohol type, i. e., a solvent comprising a mixture of alcohols such as methanol, ethanol and butanol which have suflicient volatility at room temperature to escape within a permissible time of drying. The ratio of oil to solvent may extend from 15:85 as a minimum proportion of oil to 40:60 as a maximum proportion of the oil. At the former range, the deposited film is thinner and harder (due to the increased relative proportion of other ingredients than blown castor oil); while at the latter range, the solution becomes more difficult of manufacture and maintenance.

The soap ingredient is preferably a linseed oil soap, although other soaps of the desired characteristics may be utilized. The soap should be soft in physical characteristic, to avoid hardness in the layer formed by the sealing composition; it should be chemically neutral to avoid attack or corrosion upon metal parts and to avoid any -25 to 100 grams of the selected soap. When commercial linseed oil soap of the type known as Flax Soap" is selected as the neutral soft soap, the preferred proportion is approximately grams of the soap per cc. of ethyl alcohol as solvent. Other alcohols may be utilized, care being taken to assure that their volatility is proper for the deposit of the desired film, and that they are without deleterious effect upon the materials with which they come in contact.

The aluminum stearate is preferably taken up in toluene as a'volatile solvent, in a quantity of 10 to 50 grams of aluminum stearate per 100 cc. of solvent. Preferably, the quantity of aluminum stearate is from 30 grams per 100 cc. up to the proportion for saturation.

It will be noted that the several solvents are selected as volatile agents, and with the particular preferred selection, about three minutes is required for complete volatilization at room temperature, with the deposit of the preferred type of film. At lower temperatures, a longer time is required, but a commercially effective deposit can be accomplished within a reasonable time, such as 12 to 15 minutes at zero degrees C.

Since the deposited film contains the nonvolatile constituents of the original ingredients, it may be pointed out that a preferred composition will contain from 25 to 30 percent of nonvolatile material. For each 10 parts by weight of the oil solution, from 2.5 to 6 parts of the soap component are introduced, and also2.5 to 6 parts of the stearate component.

The mixture is preferably prepared by forming the components as solutions and then mixing the aluminum stearate solution'with the castor oil solution, and then adding the soap solution. This order of addition'has been found essential with high concentrationsof stearate, in order to prevent a transfer of solvent from the stearate solution to the soap solution whereby small particles of aluminum stearate are discretely precipitated. No heating is required during the mixing, if this precaution is taken.

The composition has good adherence to metal parts, due to the specific effectiveness of the materials as sealing agents and anti-seize substances, and to their capability of coacting with one another to produce a uniform material which is able to deposit as satisfactory film. The flax soap is insoluble in gasoline, and increases the anti-seize properties of the film without building up the body of the compound. The aluminum stearate affords the desired body" and assists in preventing seizing effects. It has been found that the aluminum stearate is preferable to other compounds, including the other stearates, as it establishes a better combination of the effects of the blown oil and the soap solutions.

The composition is adapted for employment as a sealing and anti-seize compound for gasket and threaded joints, being excellently adapted for use in connection with aluminum or aluminum alloy parts and also being capable of providing a satisfactory sealing and lubricating film between and with surfaces of other metals, such as brass or steel. The composition, in the preferred form set out above, retains a plastic or resilient condition for an indefinite period of time. Thus, it is of great value for sealing threaded joints in conduit lines, pressure couplings for conduits, closing members for receptacles, etc., where there is contact with gasoline, oil, water, windshield de-icer fiuid, and other similar media. Its chemically neutral condition and absence of dissociable ingredients protects contacted metals against electrolytic or galvanizing actions.

It is obvious that other changes may b made in the composition without departing from the scope of the appended claims.

I claim:

1. A composition for producing sealing and anti-seize joints, consisting of a mixture of 10 parts of highly polymerized blown castor oil dissolved in a limited quantity of a volatile alcohol solvent, substantially 3.3 parts of a soft neutral linseed oil as a substantially saturated solution in ethyl alcohol, and substantially 3 parts of aluminum stearate as a substantially saturated solution in toluene.

2. A composition for producing sealing and anti-seize Joints, comprising 10 parts of hi y polymerized blown castor 011, 2.5 to 6 parts of a soft neutral soap, and 2.5 to 6 parts of aluminum stearate, in a solvent medium for said ingredients which is volatile at room temperature.

3..A joint prepared to resist seizing and toremain sealed against gasoline, oil and water. comprising a base structure having a metal fitting for engagement with a cooperating part, and a film upon said fitting consisting essentially of an intimate mixture of 10 parts of highly polymerized blown castor oil, 2.5 to 6 parts of a soft neutral soap, and 2.5 to 6 parts of aluminum stearate.

4. A joint prepared to resist seizing and to remain sealed against gasoline, oil and water, o prising a base structure having a metal fitting for engagement with a cooperating part, and a film upon said fitting deposited from a mixed solution containing 10 parts of highly polymerized blown castor oil solution in the form'of 25 parts of the oil in parts of solvent of alcohol type, substantially 3.3 parts of a saturated solution of a neutral soft linseed oil soap in an alcohol solvent. and substantially 3 parts of a solu tion of aluminum stearate in an aromatic solvent, said solvents being volatile at room temperature.

ARTHUR L. PARKER. 

